1. Field of the Invention
The present invention relates to an electrochromic display device and a method of manufacturing the same, and more particularly, to a method of manufacturing an electrochromic device, in which the manufacturing process steps are simplified in order to significantly improve the manufacturing process efficiency. Also provided is an electrochromic device characterized by excellent driving properties with regard to both memory properties and response properties.
2. Description of the Related Art
Generally, electrochromic display systems are based on the color variations that occur in various types of metal oxides, and organic or inorganic compounds, resulting from electrochemical reactions, particularly oxidation-reduction reactions.
An electrochromic device typically has a sandwich type structure. The electrochromic device generally comprises two glass substrates one, on each outer side; a counter electrode and a working electrode disposed between the glass substrates; an electrochromic material; and an electrolytic solution enabling the permeation of ions.
As an example, an electrochromic device can be manufactured in such a manner that a nanocrystal semiconductor material is layered onto a cathode, and the electrochromic material is subsequently adsorbed onto the nanocrystal semiconductor layer. In addition, a metal layer that can be reversibly oxidized is arranged on an anode. This electrochromic device has disadvantages in that the electrochromatic device has a slow response speed, and it does not have sufficient memory properties.
In another example, an electrochromic device can be manufactured in such a manner that the cathode is constructed as described above and an electrochromic compound, having a p-type oxidation-reduction promoter, is adsorbed onto the nanocrystal semiconducting layer on the cathode. This electro-chromic device is advantageous in that it has a fast response speed and enhanced memory properties. However, this electro-chromic device still has problems in that it is difficult to synthesize an oxidation-reduction chromophore compound, which can be adsorbed into a nanocrystal semiconductor material. In addition, the manufacturing process steps of such a device are complex.